Rainbow Electronics MAX1557 - Manual (Page 2)

MAX1556/MAX1557
16µA I Q , 1.2A PWM DC-DC
Step-Down Converters
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V IN = V INP = V SHDN = 3.6V, T A = - 40°C to +85°C. Typical values are at T A = +25°C, unless otherwise noted.) (Note 1)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
IN, INP, OUT, D2, SHDN to GND ..........................-0.3V to +6.0V
SS, D1 to GND .............................................-0.3V to (V
IN + 0.3V)
PGND to GND .......................................................-0.3V to +0.3V
LX Current (Note 1)...........................................................±2.25A
Output Short-Circuit Duration.....................................Continuous
Continuous Power Dissipation (T
A = +70°C)
10-Pin TDFN (derate 24.4mW/°C above +70°C) .......1951mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Voltage 2.6 5.5 V
Undervoltage-Lockout Threshold V IN rising and falling, 35mV hysteresis (typ) 2.20 2.35 2.55 V
No switching, D1 = D2 = GND 16 25
Quiescent Supply Current
Dropout 27 42
µA
T A = +25°C 0.1 1
Shutdown Supply Current SHDN = GND
T A = +85°C 0.1
µA
Output Voltage Range 0.75 V
IN
V
No load -0.25 +0.75 +1.75
300mA load -0.75 0 +0.75
600mA load -1.5 -0.75 0
T A = 0°C to +85°C
(Note 2)
1200mA load, MAX1556 only -2.75 -2.25 -1.25
No load -0.75 +2.25
300mA load -1.5 +1.5
600mA load -2.25 +0.50
Output Accuracy
T A = -40°C to +85°C
(Note 2)
1200mA load, MAX1556 only -4.0 -1.0
%
MAX1556 1200
Maximum Output Current
MAX1557 600
mA
T A = +25°C 0.01 0.1
D1 = D2 = GND
T A = +85°C 0.01 OUT Bias Current
For preset output voltages 3 4.5
µA
No load -0.50 +0.75 +1.75
300mA load -1.2 0 +1.2
600mA load -1.75 -0.75 +0.25
D1 = D2 = GND,
V
OUT = 0.75V at
300mA (typ),
T
A = 0°C to +85°C
1200mA load, MAX1556 only -3.25 -2.25 -1.25
No load -1.25 +2.25
300mA load -1.75 +1.50
600mA load -2.75 +0.25
FB Threshold Accuracy
D1 = D2 = GND,
V
OUT = 0.75V
at 300mA (typ),
T
A = -40°C to +85°C
1200mA load, MAX1556 only -4.25 -1.00
%
Note 1: LX has internal clamp diodes to GND and IN. Applications that forward bias these diodes should take care not to exceed
the IC’s package power-dissipation limits.